Grapevine plant named ‘KERSUS’

ABSTRACT

A new grape variety distinguished by its high vigour, circular shaped leaves, medium weight fruit clusters, early-medium harvesting time (end of August in northeastern Italy), green dorsal and ventral internodes, and resistance to downy mildew and powdery mildew.

Latin name of the genus and species of the plant claimed: Vitis viniferaL.

Variety denomination: ‘KERSUS’.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority from QZ Community PlantVariety Office (CPVO) Application No. 20183519, filed Dec. 20, 2018.

BACKGROUND

The present application relates to a new and distinct variety of grapenamed ‘KERSUS’. Our new plant resulted from a controlled cross and is aselection from crossing SK-00-1/7 (unpatented) as the seed parent withPinot Blanc (unpatented) as the pollen parent in 2005. The resultingplant was selected in 2013 when growing in a cultivated area in Udine,Italy.

‘KERSUS’ is primarily adapted to the climate and growing conditions ofthe temperate regions with average yearly temperature about 13° C.,minimum winter temperature about −20° C., annual rainfall around700-1500 mm of rain (e.g. North-Eastern Italy, Friuli). This regionprovides the necessary year-round temperatures required for it toproduce and maintain a strong vigorous plant with consistent fruitproduction.

SUMMARY

The ‘KERSUS’ variety is distinguished from other grape varieties due tothe following unique combination of characteristics: high vigour,circular shaped leaves, medium weight fruit clusters, early-mediumharvesting time (end of August in northeastern Italy), green dorsal andventral internodes, and resistance to downy mildew and powdery mildew. Acomparison of the new variety to its parents, Vitis vinifera ‘Pinotblanc’ (unpatented) and Vitis cross ‘SK-00-1/7’ (unpatented), and to thevariety ‘PINOT ISKRA’ (co-pending application Ser. No. 16/602,637) isprovided in Table 1.

TABLE 1 ‘PINOT Characteristic ‘Kersus’ ISKRA’ vigour High Medium-highgrowth Semi-erect Semi-erect habit leaf Medium, dark Very small to greencolor small, dark (upper surface) green color RHS N134A, (upper surface)very few hairs RHS N134A, in both surfaces, very few hairs circularshape, in both surfaces, small teeth pentagonal shape, medium teeth,strong blistering of upper side of blade cluster low weight, low weight,cylindrical with cylindrical with one or two one or two middle sizemiddle size wings, compact, wings, compact, globose berry, globoseberry, berry skin with berry skin with yellow-green yellow-green colorRHS color, soft flesh, 150C, soft neutral taste, no flesh, neutral fleshcoloration taste, no flesh coloration harvesting Early-mediumEarly-medium time [End of August [end of August (Middle Friuli, (MiddleFriuli, northeastern Italy)] northeastern Italy)] resistances Resistantto Resistant to downy mildew, downy mildew resistant to and to powderypowdery mildew mildew. internode Dorsal: green Dorsal: red and colorVentral: green green RHS 140B Ventral: red RHS 53A and green RHS 140BFemale Parent Male Parent Characteristic ‘SK-00-1/7’ Pinot blanc vigourMedium Medium growth Semi-erect Semi-erect habit leaf Medium, Medium,dark pentagonal green color shape, medium (upper surface) teeth, mediumRHS N134A, blistering of very few hairs upper side of in both bladesurfaces, pentagonal shape, small teeth cluster medium low weight,weight, with one or two cylindrical, wings, globose berry, compact,broad berry skin with ellipsoid berry, yellow-green berry skin withcolor, soft yellow-green flesh, neutral color RHS taste, no flesh 154C,soft coloration flesh, neutral taste, no flesh coloration harvestingMedium [early Medium [early time September September (Middle Friuli,(Middle Friuli, northeastern Italy)] northeastern Italy)] resistancesResistant to No resistance downy to downy mildew, mildew, no resistantto resistance to powdery powdery mildew. mildew internode Dorsal: greenDorsal: green color Ventral: green and red 140B Ventral: green RHS 140Band red RHS 53A

Of the many commercial cultivars known to the present inventor, the mostsimilar to the new grapevine ‘KERSUS’ is the male parent ‘Pinot blanc’,to which a comparison has been provided above.

Asexual reproduction of this new variety by grafting onto K5BB rootstockwas first performed in February 2014 in Rauscedo, Friuli Venezia GiuliaRegion, Italy, and has demonstrated that the foregoing characteristicsfor the new cultivar come true to form, are firmly fixed, and areestablished and transmitted through succeeding propagations. The newcultivar reproduces true to type.

Certain characteristics of this variety may change with changingenvironmental conditions (such as photoperiod, temperature, moisture,soil conditions, nutrient availability, or other factors). Colordescriptions and other terminology are used in accordance with theirordinary dictionary descriptions, unless the context clearly indicatesotherwise. Color designations (hue/value/chroma) are made with referenceto The Royal Horticultural Society (R.H.S.) Colour Chart, 5th edition,London, England, 2007.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a photograph showing a shoot a leaf of the new variety‘Kersus’ taken on May 24, 2017, in Rauscedo, Italy.

FIG. 2 is a photograph showing a leaf of the new variety ‘Kersus’ takenon May 24, 2017, in Rauscedo, Italy.

FIG. 3 is a photograph showing fruit of the new variety ‘Kersus’ takenon Aug. 24, 2016, in Rauscedo, Italy.

FIG. 4 is a photograph showing a plant of the new variety ‘Kersus’ takenon Aug. 24, 2016, in Rauscedo, Italy.

The color photographs show typical specimens of the new variety anddepict the color as nearly true as is reasonably possible to make thesame in a color illustration of this character. It should be noted thatcolors may vary, for example due to lighting conditions at the time thephotograph is taken. Therefore, color characteristics of this newvariety should be determined with reference to the observationsdescribed herein, rather than from the photograph alone.

DETAILED DESCRIPTION Botanical

The following detailed description of the ‘KERSUS’ variety is based onobservations of asexually reproduced progeny. The observed progeny areplants which were 3-5 years of age. The following detailed descriptionconcerns the plants growing in an open field taken in Rauscedo, Italy in2016-2018. The original plant and progeny have been observed growing ina cultivated area in Rauscedo, Italy, with medium texture soil that isrich in skeleton and alluvial in nature. Temperatures in Rauscedo, Italyrange from a high of 29° C. to a low of −2° C. Average rainfall is 822mm per year, with an average rainfall during the growing season(April-September) of 453 mm. The chart used in the identification ofcolors described herein is The R.H.S. Colour Chart, 5^(th) edition,except where general color terms of ordinary significance are used. Thecolor values were determined in August-September 2018 under naturallight conditions in Rauscedo, Italy.

-   Scientific name: Vitis vinifera L.-   Parentage:    -   -   Seed parent.—Sk-00-1/7.        -   Pollen parent.—Pinot Blanc.-   Plant:    -   -   Vigor.—High.        -   Growth habit.—Semi-erect.-   Trunk:    -   -   Diameter at 50 cm.—3.1 cm (6 yr-old plants).        -   Bark texture.—Striate.        -   Bark coloration.—RHS 187A.-   Mature cane:    -   -   Diameter.—9.6 mm.        -   Bark texture.—Ribbed.        -   Bark coloration.—RHS 179C.-   Shoot:    -   -   Opening of the shoot tip.—Fully open for young shoot.        -   Distribution of the anthocyanin coloration of the prostrate            hairs of the shoot tip.—Absent.        -   Density of prostate hair on the shoot tip.—Medium-to-high.        -   Attitude (before tying).—Semi-erect.        -   Color of the dorsal side of internodes.—Green 140B.        -   Color of the ventral side of internodes.—Green 140B.        -   Distribution of anthocyanin coloration on the bud            scales.—Absent.        -   Number of consecutive tendrils.—2 or less.-   Tendrils:    -   -   Length.—21.9 cm.        -   Diameter.—2.4 mm.        -   Color.—RHS 150A.-   Leaves:    -   -   Shape.—Circular.        -   Ratio length/width of teeth.—Small (Marsanne), both sides            convex.        -   Arrangement of lobes of upper lateral sinuses.—Absence of            sinus (Melon).        -   Blistering.—Medium-to-strong blistering of upper side of            mature blade.        -   Size of blade.—Medium (Cabernet Sauvignon); average length            121 mm; average width 181 mm.        -   Young leaf.—Color of upper surface is green RHS 134B, color            of the lower surface RHS 142C, with sparse prostrate hairs            between main veins on the lower side of blade.        -   Mature leaf.—Color of upper surface is dark green RHS N134A,            color of the lower surface RHS 140B, with sparse prostrate            hairs between main veins on the lower side of blade.        -   Mature leaf.—Three lobes.        -   Area of anthocyanin coloration of main veins on upper side            and lower of mature blade.—Absent.        -   Area of anthocyanin coloration of main veins on lower side            of mature blade.—Absent.        -   Goffering/depressions of mature blade between the main            veins.—Absent or very weak (Gamay).        -   Profile of mature leaf in cross section.—V-shaped.        -   Degree of mature leaf opening of petiole sinus.—Closed.        -   Shape of base of petiole sinus.—Brace-shaped            ({)-to-V-shaped.        -   Petiole sinus base limited by vein.—Not limited.        -   Petiole length compared to length of middle vein.—Equal            (Garnacha tinta).        -   Petiole average length.—117.5 mm.        -   Petiole color (upper surface).—RHS 145B and RHS 184D.        -   Petiole color (lower surface).—RHS 145B and RHS 184D.        -   Density of prostrate hairs on petiole.—None or very low.        -   Density of erect hairs on petiole.—None or very low.        -   Depth of upper lateral sinuses.—Absent or very shallow;            average depth of the sinus 35.2 mm.-   Flower bud:    -   -   Shape.—Round.        -   Size.—Average.        -   Color.—Light brown.        -   Bud burst.—Beginning of April in Rauscedo, Italy.-   Flowers: Fully developed stamens and fully developed gynoecium.    -   -   Insertion of 1st inflorescence.—3rd and 4th node.        -   Number of inflorescences per shoot.—1 to 2.        -   Flowering period (time of beginning of flowering).—Beginning            of June in Rauscedo, Italy.        -   Average flower diameter.—2 mm.        -   Inflorescence average length.—155 mm.        -   Inflorescence average width.—121 mm.-   Fruit:    -   -   Cluster.—Low weight (about 260 g), cylindrical with one or            two middle size wings, compact.        -   Time of beginning of berry ripening.—Early.        -   Berry shape.—Globose.        -   Berry length.—Short (about 13 mm).        -   Berry width.—Narrow (about 13 mm).        -   Berry bloom.—Medium.        -   Thickness of berry skin.—Medium-to-thick.        -   Color of skin (without bloom).—Yellow green 150C.        -   Texture.—Soft flesh.        -   Flesh color.—RHS 150C.        -   Anthocyanin coloration of flesh.—Absent or very weak.        -   Flavor.—None/neutral.        -   Berry shipping quality.—N.a.        -   Berry storage quality.—N.a.        -   Formation of seeds.—Complete.        -   Average number of seeds.—2-3.        -   Seed size.—Medium (Pinot noir, Merlot).        -   Seed color.—Brown RHS 200C.        -   Harvest time.—Early-medium (end of August in northeastern            Italy).        -   Bunch length (peduncle excluded).—Medium (about 160 mm;            Syrah).        -   Bunch width.—Narrow (about 80 mm; Riesling, Sauvignon).        -   Bunch density.—Dense.        -   Length of peduncle of primary bunch.—Very short-to-short (up            to about 30 mm; Silvaner).        -   Color of peduncle.—RHS 156A and RHS N200A.        -   Diameter of peduncle.—4-5 mm.        -   Lignification of peduncle.—Up to about the middle.        -   Berry hilium.—Visible.-   Pedicel:    -   -   Average length.—9-12 mm.        -   Average diameter.—1-1.5 mm.        -   Color.—RHS 145B.-   Grape juice characteristics:    -   -   Sugars (brix).—21.1.        -   PH.—3.4.        -   Total acidity.—6.2 g/l.        -   Tartaric acid.—6.57 g/l.        -   Malic acid.—1.89 g/l.-   Production characteristics:    -   -   Clusters per shoot.—1.42.        -   Grape production.—3467 g/plant.        -   No. of bunches/vine (at harvest).—15.2.        -   Average weight of the bunch.—262.7 g.        -   Average berry weight.—1.57 g.        -   Pruning wood weight.—690 g/plant.        -   Index of ravaz.—5.02.-   Wine produced from grapes:    -   -   Total acidity.—5.3 g/l.        -   Tartaric acid.—2.5 g/l.        -   PH.—3.37.        -   Net extract.—20.0 g/l.        -   Alcohol.—12.8 g/l.        -   Volatile acidity.—0.2 g/l.        -   Reducing sugars.—1.1 g/l.

TABLE 2 Molecular Analysis VVS2 VVMD5 VVMD7  N + 10 N + 14 N + 10 N + 16N + 12 N + 26 VVMD25 VVMD27 VVMD28 N + 6 N + 14 N + 10 N + 14 N + 20 N +28 VVMD32 VRZAG62 VRZAG79 N + 5 N + 5  N + 14 N + 20 N + 2  N + 24

Use international coding based on “N” (see European project GENRES 081—Abasis for the preservation and utilization of Vitis genetic resources)

-   Phenological characteristics (in Rauscedo, Italy):    -   -   Germination.—April 4.        -   Flowering.—June 2.        -   Veraison (change of color).—August 7.        -   Maturation.—September 9.-   Use: Wine grape.-   Disease/pest resistance: Resistance to downy mildew and powdery    mildew.

We claim:
 1. A new and distinct variety of Vitis vinifera L. plantsubstantially as illustrated and described herein.